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whats the difference between diesel and gas alternators?

A

allproroofing

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Location
rochester NY
Hey Guys,
This is my first post as a new diesel owner,.........So bare with me. I've always been a gas guy and bought my first diesel (1993 chevy k3500 dually). My voltmeter on the instrument panel goes back and forth between 12 and 14.5 volts. Thinking the regulator in the alternator is bad. Being a former gas engine guy , I have a surplus of parts in the barn and was wondering if one of my 105 amp gas alternators will work in the diesel? Whats the difference?
 
I think I had a gasser one on my truck when I bout it, when it went bad and i bought a new one I needed to get more bolts, and it was mounted with a tilt to it...
so it might work? Plug was the same as my old gassers IIRC
And welcome to DTR!
 
Thanks guys. I'll check the grounds in the morning. When I got more time , we'll get into my hard starting issues!! Replaced glow plugs , ops , fixed leaking fuel filter , new 850cca batteries and still starts harder than it should. Made up a glow plug manual push button and it helps a little , but not much.
 
Alot of guys had problems with aftermarket companies giving them alternators with gasser pulleys on them.

A gas alternator will work, just throw off your tach reading, so you can just swap pulleys.
 
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My '93 GMC 3500 volt meter was doing the same thing. I took it to Auto Zone, where they put a tester on it while running, and said it wasn't charging right. So I bough their new alternator for $120, put it on, and not much difference. Took the original one back and had them put it on the machine inside the store. They said it checked out good, but it wasn't loaded. I think my money might have been wasted. I intend to get some kind of DC amp meter and hook it up temporarily to see if there really is a problem or not. Will use the same or similar instrument to determine if glow plug circuit is actually working correctly.
 
look up battery mod,
http://www.dieseltowingresource.com/showthread.php?t=540

does voltage drop as engine warms up? if so, same problem I have. poured ice water on it and voltage comes up to normal. still working on that issue.

wiring connector:
P-white wire is tach, L-brown is voltage wire with 300-500 ohm resistance. F and S not used.

as far as I know gas or diesel should work. part numbers are mostly same- only difference I see is pully and body diameter
 
Thanks guys , I appreciate all the info. And no , my voltage doesn't drop after the engine warms up , it starts at about 12 volts , then fluctuates to 14.5 for about 30 seconds to a minute then goes back down to 12. Will do this several times in a short period of time , say thirty minutes or so.
 
Hey , anyone know if getting a replacement cdr valve is a dealer only item? I've tried every local auto parts store and none of them even know what one is. I'm guessing at 127,000 miles , mine still has the factory original. Maybe part of my hard starting problem?
 
Auto parts stores my call it a PCV instead
 
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NAPA calls it a PCV valve. Guess its kinda the same thing, just more complex then a gasser PCV.
 
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